growth spurt or something else?

Tori • Mommy to👶🏻❤ baby girl 03/30/2018, baby girl 12/31/2019

last week my baby was eating 2-2.5 oz. she just turned 3 weeks old today. all week she went from 3oz to 4oz and was super fussy, looking for more food, not napping, would only sleep if we are holding her. today i fed her a bottle with 4oz, she ate 3 then like 15 minutes later threw up about a 1 oz then promptly fell asleep. she only pooped once yesterday and today she pooped a lot (slightly runny ) is this normal or should i be concerned ?